We have examined scavenging of a superoxide by various prenyllipids occurring in thylakoid membranes, such as plastoquinone-9, alpha-tocopherolquinone, their reduced forms, and alpha-tocopherol, measuring oxygen uptake in hexane-extracted and untreated spinach thylakoids with a fast oxygen electrode under flash-light illumination. The obtained results demonstrated that all the investigated prenyllipids showed the superoxide scavenging properties, and plastoquinol-9 was the most active in this respect. Plastoquinol-9 formed in thylakoids as a result of enzymatic reduction of plastoquinone-9 by ferredoxin-plastoquinone reductase was even more active than the externally added plastoquinol-9 in the investigated reaction. Scavenging of superoxide by plastoquinol-9 and other prenyllipids could be important for protecting membrane components against the toxic action of superoxide. Moreover, our results indicate that vitamin K(1) is probably the most active redox component of photosystem I in the generation of superoxide within thylakoid membranes.
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Mater Today Bio
February 2025
Department of Orthopedics, The Third Affiliated Hospital of Shandong First Medical University (Affiliated Hospital of Shandong Academy of Medical Sciences), NO.38, Wuyingshan Road, Tianqiao District, Jinan, 250031, China.
The bacterial infection and oxidative wound microenvironment delay skin repair and necessitate intelligent wound dressings to enable scarless wound healing. The immunoglobulin of yolk (IgY) exhibits immunotherapeutic potential for the potential treatment of antimicrobial-resistant pathogens, while cerium oxide nanoparticles (CeO NPs) could scavenge superoxide dismutase (SOD) and inflammation. The overarching objective of this study was to incorporate IgY and CeO NPs into poly(L-lactide-co-glycolide)/gelatin (PLGA/Gel)-based dressings (P/G@IYCe) for infected skin repair.
View Article and Find Full Text PDFJ Mater Chem B
January 2025
State Key Laboratory of Food Nutrition and Safety, Key Laboratory of Food Quality and Healthy of Tianjin, College of Food Science and Engineering, Tianjin University of Science and Technology, Tianjin, 300457, P. R. China.
In an antioxidant peptide study, the number and position of active amino acid sites, as well as the peptides' conformation, are found to be crucial for scavenging hydroxyl radicals (˙OH). Herein, ˙the OH scavenging activity of tilapia pentapeptide (P1, YGDQY) and its analogs including P2 (YYYGDQY), P3 (YYGDQYY) and P4 (YYGPDQYY) was investigated. The results showed that the tyrosine's amount, location and the peptides' conformation played important roles in determining peptides' scavenging activity (34.
View Article and Find Full Text PDFMikrochim Acta
January 2025
Department of General Surgery, Hui Ya Hospital of The First Affiliated Hospital, Sun Yat-Sen University, Huizhou, 516081, Guangdong, China.
Self-supported ultrathin PtRuMoCoNi high-entropy alloy nanowires (HEANWs) were synthesized by a one-pot co-reduction method, whose peroxidase (POD)-like activity and catalytic mechanism were elaborated in detail. As expected, the PtRuMoCoNi HEANWs showed excellent POD-like activity. It can quickly catalyze the oxidization of colorless 3,3',5,5'-tetramethylbenzidine (TMB) to blue TMB through decomposition of HO to superoxide radicals.
View Article and Find Full Text PDFJ Colloid Interface Sci
January 2025
Department of Pharmaceutics, School of Pharmacy, Shenyang Pharmaceutical University, 103 Wenhua Road, Shenyang, Liaoning Province 110016, PR China. Electronic address:
Liver fibrosis is a common pathological stage in the development of several chronic liver diseases, and early intervention can effectively reverse the developing process. Excessive reactive oxygen species (ROS) can promote the activation of hepatic stellate cells (HSCs), but existing treatments have not addressed this problem. In this study, different metal-based mesoporous polydopamine (MPDA) was prepared by the soft template method, and their free radical scavenging abilities, as well as the efficacy and safety of the carriers were investigated, so as to select Cu-coordinated MPDA (CMP) as the optimal nanocarrier.
View Article and Find Full Text PDFBiomaterials
December 2024
Department of Nuclear Medicine and PET Center, The Second Affiliated Hospital of Zhejiang University School of Medicine, Hangzhou, China; Institute of Nuclear Medicine and Molecular Imaging of Zhejiang University, Hangzhou, China; Key Laboratory of Medical Molecular Imaging of Zhejiang Province, Hangzhou, China; Key Laboratory for Biomedical Engineering of Ministry of Education, Zhejiang University, Hangzhou, China. Electronic address:
Alzheimer's disease (AD) is the most prevalent neurodegenerative disorder globally, with no effective treatment available yet. A crucial pathological hallmark of AD is the accumulation of hyperphosphorylated tau protein, which is deteriorated by reactive oxygen species (ROS) and neuroinflammation in AD progression. Thus, alleviation of ROS and inflammation has become a potential therapeutic strategy in many studies.
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